Anyone who follows Innovation Origins will know that there is a medieval remedy that helps against infections that can no longer be combated with antibiotics. British researchers recently demonstrated that a 1,000-year-old eye ointment made from onion, garlic, wine, and bile salts kills bacteria that have become immune to antibiotics. But that does not mean that research into more modern tools has become superfluous. For example, a consortium of Dutch and Chinese scientists has been able to develop a smart nanoparticle that is capable of finding its own route to an infection in the body and killing the bacteria.
Such nanoparticles can eventually become an important tool in the fight against antibiotic-resistant infections, says Groningen professor Henny van der Mei, who specialises in biomaterial related biofilms and infections.
Antibiotics have difficulty penetrating to the core of a bacterial infection because the bacteria are enveloped in a layer of mucus. This only kills bacteria on the outside of the infection. The now developed nanoparticle is able to penetrate to the core of the infection. The particle then also ensures that bacteria are spread throughout the body, so they can be better killed by immune cells and existing antibiotics. “As far as we can see, this is the first smart nanoparticle that has both of these functions,” says Van der Mei.
How does it work?
The researchers introduced the nanoparticle into mice followed by an antibiotic and saw through a see-through glass in the abdomen of the mouse that it was able to find a route to the infection through the bloodstream itself. In the acidic environment of a bacterial infection, the particle is positively charged, allowing it to bind with the negatively charged bacteria. Bacteria are loosened from the infection so that they can be fought better in other parts of the body. “Spread bacteria can be more easily removed from the blood circulation by immune cells than when they live close together at an infection site,” says Van der Mei. “And when the bacteria are spread throughout the body, it increases the efficacy of existing antibiotics.”
Problem is underestimated
Infections caused by bacteria can be fought with antibiotics. These kill the bacteria or inhibit their growth. However, a bacterium can become insensitive to the antibiotic if it is used frequently. In these resistant bacteria antibiotics no longer help. According to Van der Mei, the danger of this is often underestimated. “If we don’t act, antibiotic-resistant infections threaten to become the leading cause of death worldwide by the year 2050. That’s why it’s important to be careful with the use of antibiotics and to find new ways to combat bacterial infections”.